阅读说明：本技术 一种植物源性农产品中农药残留检测方法 (Method for detecting pesticide residue in plant-derived agricultural products ) 是由 郭平 王栋 万建春 喻俊磊 张威 吴遥 于 2020-12-28 设计创作，主要内容包括：本发明属于农药检测技术领域,公开了一种植物源性农产品中农药残留检测方法。本发明的植物源性农产品中农药残留检测方法使用农药残留快速净化管对待检农产品进行前处理,所述净化管采用塑料离心管作为主体材料,离心管内填装有PSA材料、石墨化碳黑材料(CARB)、高分子亲水亲酯平衡材料(PLS)和无水硫酸镁材料,这些材料通过优化配比,均一混合,作为植物源性农产品中农药残留检测时样品前处理的净化吸附剂,为植物源性农产品农药残留的合理、有效监控提供了重要的技术支撑。(The invention belongs to the technical field of pesticide detection, and discloses a method for detecting pesticide residues in plant-derived agricultural products. The method for detecting pesticide residues in plant-derived agricultural products uses a rapid pesticide residue purification tube to pretreat agricultural products to be detected, the purification tube adopts a plastic centrifuge tube as a main body material, a PSA material, a graphitized carbon black material (CARB), a macromolecular hydrophilic ester balance material (PLS) and an anhydrous magnesium sulfate material are filled in the centrifuge tube, the materials are used as a purification adsorbent for sample pretreatment during pesticide residue detection in the plant-derived agricultural products by optimizing the proportion and uniformly mixing, and important technical support is provided for reasonable and effective monitoring of the pesticide residues in the plant-derived agricultural products.)

1. The method for detecting the pesticide residue in the plant-derived agricultural products is characterized in that the agricultural products to be detected are pretreated by using a pesticide residue rapid purification tube, the purification tube adopts a plastic centrifuge tube as a main body material, and a PSA material, a graphitized carbon black material, a high-molecular hydrophilic ester balance material and an anhydrous magnesium sulfate material are filled in the centrifuge tube.

2. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the pretreatment comprises extracting a plant-derived agricultural product sample with acetonitrile, adding a supernatant into the rapid pesticide residue purification tube, shaking and mixing, and centrifuging.

3. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the pretreatment comprises taking 10g of plant-derived agricultural product samples, performing vortex extraction with 10mL of acetonitrile, and adding 1g of NaCl and 4g of MgSO₄And mixing by vortex, centrifuging, taking out 1mL of supernatant, adding the supernatant into the pesticide residue rapid purification tube, shaking, mixing and then centrifuging.

4. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the PSA material is ethylenediamine-N-propyl bonded silica gel.

5. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the pore volume of the graphitized carbon black material is 0.8cm³/g-1.2cm³Per g, specific surface area of 250m²/g-400m²/g。

6. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the macromolecular hydrophilic ester equilibrium material is a cross-linked polystyrene-divinylbenzene polymer having a polar N atom on the surface.

7. The method for detecting pesticide residues in plant-derived agricultural products as claimed in claim 1, wherein 45-55mg of PSA material, 2.5-8mg of graphitized carbon black material, 20-30mg of polymeric hydrophilic ester equilibrium material, and 135-165mg of anhydrous magnesium sulfate material are filled in a centrifugal tube in the rapid pesticide residue purification tube.

8. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein 50mg of PSA material, 7.5mg of graphitized carbon black material, 25mg of high-molecular hydrophilic ester equilibrium material and 150mg of anhydrous magnesium sulfate material are filled in a centrifugal tube in the pesticide residue rapid purification tube.

9. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the specification of the plastic centrifuge tube is 2 mL.

10. The method for detecting pesticide residues in plant-derived agricultural products according to claim 1, wherein the plant-derived agricultural products are vegetables, fruits, and cereals.

Technical Field

The invention relates to the technical field of pesticide detection, in particular to a method for detecting pesticide residues in plant-derived agricultural products.

Background

The pesticide residue is produced and widely used, and is not decomposed and remained on the fruits and vegetables within a certain time after being used, and the residual pesticide is probably transmitted to the human body finally through a food chain. With the improvement of public food safety consciousness, quality safety of edible agricultural products is more and more concerned at present, in particular to the problem of pesticide residues in vegetables. Therefore, it is necessary to effectively monitor and manage the pesticide residue.

However, the processing process of the pesticide residue detection sample is complex, and for an inspection and detection mechanism, the task of randomly inspecting the pesticide residue of vegetables in food safety supervision every year is very heavy, and the inspection rate and the rejection rate are high. In order to reduce the burden of a detection mechanism and ensure the food safety of people, a rapid and accurate pesticide residue determination method is established, and the control of the detection quality is very important. An efficient, accurate and universal pesticide residue measuring method is also urgently needed by an inspection and detection mechanism so as to solve the difficulties in the aspects of personnel, expenses, efficiency and the like in actual work.

The pretreatment is carried out on the agricultural products to be detected, interference is eliminated, and the method is very important for obtaining accurate and reliable detection results. Chinese patent CN106596801A provides a purification adsorbent for sample pretreatment in fruit and vegetable pesticide residue detection, which comprises 0-50 parts of C18, 0-50 parts of graphitized carbon black and 10-50 parts of Fe₃O₄@SiO₂@ PSA. The time consumed by the purification adsorbent for sample pretreatment is reduced by 61.1 percent compared with the time consumed by the QuECHERS which is a rapid pretreatment method widely applied in the prior art, but 70min is required to complete 5 minutes simultaneouslyThe efficiency of the pretreatment process of 0 samples still needs to be improved. In addition, the use of Fe is required in the invention₃O₄@SiO₂@ PSA, is relatively costly. Therefore, a sample pretreatment method with high treatment efficiency, simple operation and low cost is needed in the field of pesticide residue detection.

Disclosure of Invention

The invention aims to overcome the defects of the background technology and provide a method for detecting pesticide residues in plant-derived agricultural products. The pesticide residue detection method of the invention uses a special pesticide residue rapid purification tube to carry out pretreatment on agricultural products to be detected, the purification tube contains a silica gel bonded PSA material, a graphitized carbon black material, a macromolecular hydrophilic ester balance material and an anhydrous magnesium sulfate material, and the materials are uniformly mixed through optimized proportioning and are used as a purification adsorbent for sample pretreatment during pesticide residue detection in plant-derived agricultural products, thereby providing an important technical support for reasonable and effective monitoring of pesticide residues in the plant-derived agricultural products.

In order to achieve the purpose of the invention, the method for detecting pesticide residues in plant-derived agricultural products pretreats the agricultural products to be detected by using a pesticide residue rapid purification tube, wherein the purification tube adopts a plastic centrifuge tube as a main body material, and a PSA material, a graphitized carbon black material (CARB), a high molecular hydrophilic ester equilibrium material (PLS) and an anhydrous magnesium sulfate material are filled in the centrifuge tube.

Further, the pretreatment is that a plant-derived agricultural product sample is extracted by acetonitrile, and then supernatant is added into the pesticide residue rapid purification tube to be vibrated, mixed and centrifuged.

Further, the pretreatment is to take 10g of plant-derived agricultural product sample, perform vortex extraction by using 10mL of acetonitrile, add 1g of NaCl and 4g of MgSO₄And mixing by vortex, centrifuging, taking out 1mL of supernatant, adding the supernatant into the pesticide residue rapid purification tube, shaking, mixing and then centrifuging.

Further, the PSA material is ethylenediamine-N-propyl bonded silica gel.

Further, the pore volume of the graphitized carbon black material in the present invention is 0.8cm³/g-1.2cm³Per g, specific surface area of 250m²/g-400m²(ii) in terms of/g. The material with the specification has more normal six-membered ring sheets, has stronger affinity to pigment plane molecules, and has stronger retention effect on macromolecular impurities.

Further, the macromolecular hydrophilic ester equilibrium material (PLS) in the invention is a crosslinked polystyrene-divinylbenzene polymer containing polar N atoms on the surface. Since the surface of the material has polar groups and nonpolar groups, part of medium-polarity impurities can be adsorbed by nonpolar dispersive force, and interferents with polar groups can be adsorbed by polar interaction including Hydrogen Bonding (Hydrogen Bonding), Dipole moment (Dipole/Dipole), Induced Dipole moment (Induced Dipole/Dipole), Pi-Pi (Pi-Pi) and other various interaction forces.

Further, 45-55mg of PSA material, 2.5-8mg of graphitized carbon black material, 20-30mg of macromolecular hydrophilic ester balance material and 135-165mg of anhydrous magnesium sulfate material are filled in a centrifugal tube in the pesticide residue rapid purification tube.

Preferably, 50mg of PSA material, 7.5mg of graphitized carbon black material, 25mg of macromolecular hydrophilic ester equilibrium material and 150mg of anhydrous magnesium sulfate material are filled in a centrifugal tube in the pesticide residue rapid purification tube.

Further preferably, the specification of the plastic centrifuge tube is 2 mL.

The preparation method of the rapid pesticide residue purification tube can accurately weigh PSA material, graphitized carbon black material, macromolecular hydrophilic ester balance material and anhydrous magnesium sulfate material into the plastic centrifugal tube by a ten-thousandth precision balance.

Furthermore, the plant-derived agricultural products are agricultural products such as vegetables, fruits, grains and the like.

Compared with the prior art, the method for detecting pesticide residues in plant-derived agricultural products pretreats the samples to be detected by using the specially-made purification tube, can reduce the interference of other substances except pesticides on the detection result to the maximum extent, can be used for detecting various pesticide residues, can improve the detection efficiency, can ensure the reliability of the detection result, reduces the risk of a detection mechanism, provides important technical support for reasonable and effective monitoring of the pesticide residues in the plant-derived agricultural products, and has good social benefits.

Drawings

Fig. 1 is a schematic diagram of the pesticide residue rapid purification tube of the invention, wherein 1 is a plastic centrifuge tube, and 2 is a material filled in the centrifuge tube.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. It is to be understood that the following description is only illustrative of the present invention and is not to be construed as limiting the present invention.

The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The PSA material is ethylenediamine-N-propyl bonded silica gel, has both polar adsorption and anion exchange, can adsorb impurities by anion exchange or polar adsorption, and can form hydrogen bonds with molecules having-OH, -NH or-SH functional groups. The PSA material has the advantages of selective retention of anionic organic compounds (such as compounds containing carboxyl and phenolic hydroxyl), and chelating action with metal ions, is used for extracting metal ions, and mainly adsorbs interferents such as organic acid, polysaccharide, carbohydrate, metal ions and the like in the detection process of pesticide residues.

Unless otherwise specified, the PSA material in the embodiments of the present invention has a particle size of 50um, a pore size of 60 angstroms, and a specific surface area of 500m²The method is characterized in that the method comprises the following steps of chemically bonding full-porous spherical silica gel and a corresponding silanization reagent in a nonpolar organic solvent, and carrying out corresponding tests on the product obtained by bonding such as drying weight loss, ion exchange capacity, retention performance and the like. Wherein, the drying weight loss process is that a certain amount of filler is dried in a 120 ℃ oven such as a drying dish, and the product is weighed, wherein (the original weight-the dried weight)/the original weight is less than or equal to 2.0 percent, namely the product is qualified. The ion exchange capacity is tested by adopting a chemical titration method according to GB/T5760-2000, and the result shows that the maximum regeneration capacity is more than or equal to 2.0, and the regeneration capacity of weak base groups is more than or equal to 1.8, namely the product is qualified. The retention performance test comprises the following basic steps:

the dried PSA packing is packed into a chromatographic column by a dry packing method, and the chromatographic column requires 150mm multiplied by 4.6 mm. The machine system is washed by isopropanol at the flow rate of 2mL/min for about 60min, connected with a chromatographic column, and replaced by a mobile phase which is washed at the flow rate of 1mL/min until the baseline is stable.

Wherein the detection sample is toluene, nitrobenzene, 2-nitrobenzyl ether (o-nitroanisole); the chromatographic conditions were as follows:

mobile phase: n-hexane: ethanol 98: 2

Detection wavelength: 254nm

Flow rate: 1mL/min

Sample introduction amount: 2 μ L

Column temperature: 30 deg.C

The retention time of the test compound is judged, and the toluene is more than 1.5min, the nitrobenzene is more than 2.5min, and the o-nitroanisole is more than 4.5min, namely the test compound is qualified.

The graphitized carbon black (CARB) has a lamellar structure and better retains planar molecules. Green leaf vegetable samples often contain a large number of pigments, such as chlorophyll, lutein, carotenoids, etc., which often affect pesticide residue analysis and can harm the analytical instrumentation and therefore need to be removed. The graphitized carbon black of the invention has the best retention of the interferents and is an indispensable adsorbent in pesticide residue analysis.

The graphitized carbon black material of the invention adopts a method of discontinuous salt adding and fractional temperature rise inert gas protection calcination, which is different from the traditional one-time calcination method, the method of the invention organizes the internal structure of the material by adding inorganic salts such as Na salt, K salt and the like in the calcination process through the space occupation effect, and generates the novel stony desertification carbon black material with reasonable pore volume, uniform structure and large specific surface area. The pore volume of the conventional graphitized carbon black material is 0.2cm³/g-0.6cm³A specific surface area of 40 m/g²/g-200m²G, whereas the pore volume of the graphitized carbon black material of the present invention is 0.8cm³/g-1.2cm³Per g, specific surface area of 250m²/g-400m²The new material has more normal six-membered ring sheets, has stronger affinity to pigment plane molecules and has stronger retention effect on macromolecular impurities.

The prepared graphitized carbon black is subjected to atrazine recovery rate test, mainly, an atrazine standard substance is dissolved in 10mL of acetonitrile, the obtained solution passes through a solid phase extraction column filled with 500mg of graphitized carbon black, effluent liquid is received, the volume is determined to be 1mL after nitrogen blowing concentration, liquid chromatography detection is carried out, and the recovery rate is qualified when being 85% -105%.

Unless otherwise stated, the macromolecular hydrophilic ester equilibrium material (PLS) in the embodiment of the present invention is a crosslinked polystyrene-divinylbenzene polymer having polar N atoms on the surface, because the surface has polar groups and nonpolar groups, part of medium polar impurities are absorbed by nonpolar dispersion force, while the polar interaction including Hydrogen Bonding, Dipole moment, Induced Dipole moment, Pi-Pi and other various interaction forces adsorbs interferents with polar groups, which are often atoms with large differences in electronegativity, and the electron cloud has different density among the atoms to make the functional group polar, this property in turn allows the interferent with polar functionality to interact with the polar functionality on the adsorbent.

The preparation method of the hydrophilic and lipophilic balance material (PLS) provided by the invention can be as follows:

putting n-hexane into a 10L reaction kettle, adding spherical polystyrene, uniformly stirring, adding a polar functional group reagent and an initiator, reacting for 20 hours at 70 ℃, cooling to room temperature, filtering, washing a product with a large amount of methanol, putting a filler into an oven, and drying for 24 hours at 80 ℃ to obtain the product.

The method is characterized in that the hydrophilic ester equilibrium material obtained by preparation is subjected to chloramphenicol recovery rate test in meat, and the main process is as follows:

(1) adding 5g of meat sample and 20mL of ethyl acetate into a 50mL plastic centrifuge tube;

(2) homogenizing at 10000rpm for 2min, centrifuging at 4000rpm for 5min, and transferring the ethyl acetate extractive solution into 50mL test tube with plug;

(3) extracting with 20mL ethyl acetate once again, combining organic phases, and performing rotary evaporation at 35 ℃ to obtain a solution;

(4) adding 10mL of 5% methanol aqueous solution and 10mL of n-hexane into the test tube, mixing for 1min by using a vortex mixer, discarding the n-hexane layer, and purifying the lower layer solution (water layer) by using an SPE column.

SPE column purification (polymer matrix hydrophilic lipophilic balance column, 60mg/3mL) conditions were as follows:

(1) and (3) activation: activating by 3mL of methanol, and balancing by 3mL of water;

(2) loading: adding the solution to be purified into the small column, and discarding the effluent liquid;

(3) leaching: sequentially leaching the small column by using 3mL of water and 3mL of 30% methanol water solution, discarding the leaching solution, and then pumping the small column to be dry;

(4) and (3) elution: eluting with 6mL of methanol, and collecting eluent;

(5) re-dissolution: the eluent is evaporated at 35 ℃ to be nearly dry, 1mL of mobile phase is used for dissolving residues, the solution is filtered by a microporous membrane and then is analyzed by HPLC, and the liquid chromatography conditions are as follows:

a chromatographic column: diamonsil C18(2), 250X 4.6mm, 5 μm

Mobile phase: methanol/water 40/60(V/V)

Flow rate: 1.0mL/min

Column temperature: 30 deg.C

A detector: 280nm

Sample introduction amount: 20 μ L

And evaluating the recovery rate result, wherein when the addition amount is 1mg/kg, the recovery rate of the chloramphenicol is qualified when 80-120%.

The purity of the anhydrous magnesium sulfate material is as high as possible, the anhydrous magnesium sulfate material is mainly used for adsorbing a small amount of moisture in a purifying solution, when moisture exists, the adsorption effect of a PSA filler can be influenced, even if the moisture exists, the quantitative result of GC-MS can be influenced, meanwhile, the anhydrous magnesium sulfate is ensured to be clean, the detection is influenced by impurity dissolution, the production process is that the quantitative anhydrous magnesium sulfate is taken out of a muffle furnace and calcined at 550 ℃ for 24 hours to obtain a product, a blank test is carried out on the product, the process is that 4g of anhydrous magnesium sulfate is taken out of a 50mL centrifuge tube, 20mL of acetonitrile is added twice, the product is oscillated for 1min, the supernatant is obtained through centrifugation, a 35 ℃ water bath is reduced in pressure and evaporated to dryness, the product is cooled, normal hexane is used for fixing the volume to 1mL, GC-MS is used for detection, and the detection is required.

The technical features of the embodiments of the present invention may be combined with each other as long as they do not conflict with each other.

Example 1

A method for detecting pesticide residues in plant-derived agricultural products comprises the step of pretreating the agricultural products to be detected by using a rapid pesticide residue purification tube, wherein the purification tube adopts a 2mL plastic centrifuge tube as a main body material, and 50mg of PSA material, 7.5mg of graphitized carbon black material, 25mg of macromolecular hydrophilic ester balance material and 150mg of anhydrous magnesium sulfate material are filled in the centrifuge tube.

The pretreatment method of the agricultural product to be detected comprises the following steps: 10g of sample +10mL of acetonitrile was taken and mixed by vortexing1 min; add 1g NaCl and 4g MgSO₄Vortex mixing for 1min, centrifuging at 8000rpm for 2 min; taking out 1mL of supernatant in a purification tube, mixing by vortex, and centrifuging at 10000rpm for 2 min.

And taking out the clear liquid after pretreatment, filtering and analyzing by GCMS.

Example 2

Based on the material ratio of AOAC2007.01 and EN 15662 detection methods, a typical green vegetable spinach is selected as a sample, pretreated and detected as described in example 1, dichlorvos, fenamiphos, trifluralin, phorate, a-hexachlorobenzene, dimethoate, beta-hexachlorobenzene, lindane, quintozene, ethoprophos, delta-hexachlorobenzene, chlorothalonil, clozapon, iprobenfos, chlorpyrifos-methyl, parathion-methyl, heptachlor, tolclofos-methyl, pyralid, fenitrothion, pirimiphos, malathion, fenthion, dicofol, chlorpyrifos, parathion, pyrimidophos, heptachlor epoxide, triadimenol, procymidone, methidathion, a-endosulfan, chlordane, p '-DDE, isodina, beta-endosulfan, p' -DDD, Using pesticide compounds such as o, p-DDT, ethion, triazophos, endosulfan, p' -DDT, thiophenyl, thiotepa, cyfluthrin, cypermethrin, fenvalerate, difenoconazole, deltamethrin and the like as probes, carrying out GC-MS detection, adjusting the material quality, calculating a recovery result, and determining the optimized proportioning combination through the influence of a PSA material and a polymer material on the recovery rate and the matrix effect of the pesticide compounds, the influence of a graphitized carbon black material on the recovery rate and the matrix effect of the pesticide compounds and the influence of the color of the purifying liquid.

(1) The PSA dosage is optimized, and the experimental dosage is as follows:

A：25mg PSA，25mg PLS，7.5mg Carb，150mg MgSO₄；

B：50mg PSA，25mg PLS，7.5mg Carb，150mg MgSO₄；

C：100mg PSA，25mg PLS，7.5mg Carb，150mg MgSO₄；

D：150mg PSA，25mg PLS，7.5mg Carb，150mg MgSO₄；

the recovery and matrix effect results were as follows:

amount of PSA used	25mg	50mg	100mg	150mg
					Number of matrix effects: (>120％)	5	2	2	2
Quantity of recovery: (<80％)	4	5	7	8

And (4) integrating the balanced matrix effect and the number of the recovery rate compounds in the results to determine the optimal dosage of 50 mgPSA.

(2) The PLS dosage is optimized, and the experimental dosage is as follows:

A：50mgPSA，10mg PLS，7.5mg Carb，150mg MgSO₄；

B：50mg PSA，25mg PLS，7.5mg Carb，150mg MgSO₄；

C：50mgPSA，50mg PLS，7.5mg Carb，150mg MgSO₄；

D：50mg PSA，75mg PLS，7.5mg Carb，150mg MgSO₄；

the recovery and matrix effect results were as follows:

dosage of PLS	10mg	25mg	50mg	75mg
					Number of matrix effects: (>120％)	6	2	2	1
Quantity of recovery: (<80％)	3	5	8	9

And (3) combining the results to balance the matrix effect and the number of the recovery compounds, and determining the optimal dosage of 25 mgPLS.

(3) The CARB dosage is optimized, and the experimental dosage is as follows:

A：50mgPSA，25mg PLS，2.5mg Carb，150mg MgSO4

B：50mg PSA，25mg PLS，7.5mg Carb，150mg MgSO4；

C：50mgPSA，25mg PLS，15mg Carb，150mg MgSO4

D：50mg PSA，25mg PLS，30mg Carb，150mg MgSO4

among the compounds selected by the invention, the pentachloronitrobenzene, the chlorothalonil, the chlorpyrifos and the difenoconazole are plane structure compounds which are easily adsorbed by graphitized carbon black, so that the recovery rates and the whole matrix effect of the compounds are particularly concerned, and the results are as follows:

CARB dosage	2.5mg	7.5mg	15mg	30mg
					Number with matrix effect: (>120％)	5	2 are provided with	2	1
Recovery rate of pentachloronitrobenzene	102.45％	85.32％	70.56％	55.61％
					Recovery rate of chlorothalonil	90.12％	75.34％	60.67％	48.18％
Recovery rate of chlorpyrifos	107.63％	87.68％	77.87％	65.34％
					Recovery rate of difenoconazole	106.51％	90.90％	89.76％	70.81％

And (4) combining the balanced matrix effect and the recovery rate in the results, and determining the optimal using amount of 7.5mg of CARB.

And for the graphitized carbon black dosage, the color contrast of the purified sample is considered at the same time, wherein the color of 7.5mg of CARB is obviously lighter than 2.5mg of CARB and only slightly darker than 30mg of CARB and 15mg of CARB, and 7.5mg of CARB is determined as the optimal dosage by comprehensively balancing the matrix effect and the recovery rate result.

It will be understood by those skilled in the art that the foregoing is only exemplary of the present invention, and is not intended to limit the invention, which is intended to cover any variations, equivalents, or improvements therein, which fall within the spirit and scope of the invention.